Outlet box for wallboard



United States Patent Q OUTLET BOX FOR WALLBOARD John R. Miller, Sherman,Tex. Application November5, 1957, Serial No. 694,617 1 Claim. '(Cl.220-45 This invention relates to electrical outlet boxes and moreparticularly has reference to an outlet box designed for mounting in anopening formed ina relatively brittle wall material, such asplasterboard and various other types of wallboard finding increasingfavor in building construction, in the erection of dry wall partitionsand other interior walls of houses.

Hereinafter, the term wallboard will be used in referring to the type ofwall material in which the outlet box is particularly well adapted formounting. However, it will be understood that this term is to be con:sidered as being used in the generic sense, to embrace all types of wallcoverings in which an opening can be formed suitable for receiving anoutlet box, and which have-a sufficient thickness and rigidity to permitclamping engagement of the outlet box support means with the covering.

It is very difiicult to mount electrical outlet boxes in wallboard, andthis is due particularly to the brittle characteristics of wallboard,which is prone to chipping about. the edges of an opening formedtherein, cracking, etc.

It is desirable, of course, to provide means that will permit awallboard of'the type described to support an outlet box at any locationdesired, in view of the fact that in many instances it is desired todispose the outlet box at a location at which'it cannot be attached to astud or similar framingmember of the wall or partition.

In view of the above, the main object of the present invention is toprovide a generally improved outlet box that will be p-articularlydesigned for mounting in an opening of apiece of wallboard at anydesired location.

Another object is to'provide anoutlet box of the type describedwhichwill have an improved clampingmeans, especially' designed to firmly gripopposed edges of the opening in which the outlet box is disposed.

Yet another object is to novelly form the clamping means in such manneras to permit it to adjust itself to different thicknesses of wallboard,while at the same time assuring a firm clamping engagement with theWallboard in every instance.

Yet another object of importance is to locate the clamping means in sucha manner as not to interfere with the wires and other electrical items,such as switches, receptacles, etc., that are to be mounted within theoutlet box.

A further object is to provide, in the clamping means, a constructionsuch that movable clamp elements will normally be retracted tofacilitate insertion of the outlet box in the opening, but will beswiftly adjustable to clamping positions.

Another object of importance is to so design the clamping means thatshould it ever be desired to remove the outlet box, the clamping meanscan be swiftly adjusted to releasing positions for withdrawal of theoutlet box from the opening.

Other objects will appear from the following description, the claimappended thereto, and. from the annexed F ice 2 drawing, in which likereference characters designate like parts throughout the several views,and wherein:

Figure 1 is a longitudinal sectional view through an outlet boxaccording to the present invention, with the clamping means in grippingengagement with the wall;

Figure 2 is a view like Figure 1 inwhic'h' the clamping means is in itsretracted position, the outlet box being shown as it appers while it isbeing inserted in the opening of the wall; I

Figure 3 is a top plan view of the outlet box per se with the movableclamping'jaw removed;

Figure 4 is a detail sectional View substantially on line 44 of Figure1; and

Figure 5 is a perspective view, on an enlarged scale, of one of themovable clamping jaws per se.

Referring to the drawing in detail, designated at '10 is a wallboard,which might be plasterboard or other typeof wall surfacing material orpaneling. Designated generally at 12 is the outlet box constituting thepresent invention, and in Figures 1 and 2 said outlet box is shownpositioned within an opening 14" formed in wall 10.

The opening 14 is made slightly larger than the open front, sheet metalcontainer portion or body 16 of the outlet box.

The body 16, in a typical arrangement, would be-of rectangularconfiguration, and has a back wall 18 merging into diagonally extendingor sloped corner portions 20 having threaded openings 22, said cornerportions in turn merging into the end walls 24 of the body.

A pair of right-angularly shaped, fixed, clamping jaws 26 are secured byscrews 28 tothe respective end walls 24, withone leg 27'of each jaw 26being fiu'sh with-the open front of the body 16. The legs 27 arecoplanar with said open front, as will be seen from Figures 1 and 2,providing for a flush mounting of the receptacle within' the opening 14(see Figure 1). The other legs 25 of the fixed jaws 26 are inface-to-face contact with the outer surfaces of the end walls 24, andhave smooth-walled openings receiving the screws 28 and registeringwiththe threaded openings of the walls 24.

In some commercial embodiments, the fixed jaws 26 would be integral withthe end walls 24,. that is, the fixed jaws would merely compriseoutwardly directed flanges or lips integrally formed on the front edgesof the walls 24 and bent outwardly to form the legs 27. Insuch an event,there would of course still be fixed jaws on op posite ends of the body16, bearing against the wall 10 at opposite ends of the opening 14.

In closely spaced relation to the fixed jaws are slots 30 formed in endwalls 24 and extending transversely of said end walls as shown in Figure3. Movable, angular clamping jaws 32 are loosely pivotally engaged inthe slots 30. The movable clamping jaws have inner legs 33 disposedwithin the container portion, said inner legs merging into distal endportions 34 which are at a wide obtuse angle to the inner legs 33.

Formed in the end portions 34 are transverse slots or openings 36,receiving connecting screws 37. Openings 36 are smoothwalled, andloosely receive the screws 37 so that the screws have a limited amountof rocking movement designed to permit the screws to remain coaxiallyaligned with and threadedly engaged in the openings 22, during limitingrocking movement of the movable clamping jaws to different positions.

As shown to particular advantage in Figures 4 and 5, the inner legs 33of the movable clamping jaws are relatively narrow. At their proximalends, they are formed with short angular extensions 38 which are of awidth equal to that of the inner legs 33. Extensions 38 in turn mergeinto wide outer legs 39 of the movable clamping jaws. These are ofsubstantially greater width than the inner legs 33, that is, the outerlegs 39 of the movable x 3 b r b in dimension in a transversely of theoutlet box, than the corresponding dimensions of the inner legs. Thisprovides a otflthe outer legs 32 mi fimwfif b w t o' x A; j 38 at thejuncturebeinncr.legsl3 9,33 and ina preferred 33, that is, legs 33, 39are at an angle to slightly greaterIthanQBO degrees. TheJouter disposedwholly outside the inner legs whol- ,jawaare mountedfor rocking-movementtransversely of and disposed sub lathe planeoftheendwalls as will be ycomparison of Figures 1 and2. use QtgihfldflYiDG, originally the movableclamping I a i theouter. legs 39; are in closely spaced relation, can:fully .oralmost fully inface-to-face contact rig wwlfiblmhousht n closePro o e walls 24 Q'Iightening of the screws 31 willincrease the clampingent of wall at opposite ends of opening 14 betweenthe fixed and movablejaws, and of course, the clamping legs of the fixed and movebleljaws ateach endof the outlet box may be varied without loss of the clampingactions, accommodating the to, difierentzwall thicknesses. Shoultiiteverbe desired to remove the outlet box, one need merely retract the screws37 out of the openings 22, which themovable clamping jaws to swing backito thein Figure 2 positions. This eliminates, the clamping action andpermits withdrawal of the outlet box. It is apparent that the inventionis not neces- 'sarily confined to the specific use or uses thereofdescnbed above, since it maybe utilized for any purpose to which it maybe suited. Nor is the invention to be necessarily to the specificconstruction illustrated and de- I the outeflegs are at aslight obtuseangle swung to their Figure 2 positions. In these scribed, since sucheonstructi is only intended to be i1- lustrative of the principles ofoperation and the means presently devised to carry out said principles,it being considered that the invention comprehends any minor change inconstruction that may bepermitted within the scope of the appendedclaim.

Whatisclaimedis:

An electrical outlet box including a back wall, opposed end walls, andopposed sidegwalls, said box having an open front, each of said endwalls including a corner portion lying at an obtuse angle'both to theback wall and to the remaining portion of the end wall, said portionsextending the full width of the end walls at the juncture thereofwiththe back-wall,-said corner portion each having a threaded opening,screws engaged in each of the openings, said end walls each including afixed clamping jaw projecting outwardly at the front of the box so as tobear against the outer face, of the; wall in which the box is mounted,said end walls having transverseslots formed therein intermediate theirends, a movable clamping jaw for eachof said end walls, said clampingjaws each having an outer, leg and an, inner leg, said outer and innerlegs being integrally formed at a slightly obtuse angle relative to eachother, said inner legs being disposed throughout their lengths, at theintcrior of said boxand having relatively short extensions at theproximal end portions thereof at the juncture thereof with said louter,

legs, said short extensions being positioned in said slots,

against the inner surface of wall 10. Legs33, 1

said inner legs having distal end portions inclined at a shallow obtuseangle to the, remaining portions thereof, said distal end portions beingnormally positioned sub stantially parallel to the respectivecornerportions adjacent thereto, said inner legs having substantially the samelongitudinal dimension as the distance between said slots and saidbackwall, and saiddistal end; portions having inwardly from their distalextremities transverse, curved slots each of which opens at one end uponone longitudinal edge of'the distal end portion, whereby said legs areengaged with said screws and thetightening of said screws draws saidinner legs into close proximity with said end walls, with the cornerportions close to and substantially parallel with said distal endportions, and causes :said

outer legs to press against the inner surface of the wall in which thebox is mounted.

Zingone May 8, 1956

